The U.N. says nearly a billion people go to bed hungry every night. At the same time, hundreds of millions of others are obese. An activist and author says solving those twin crises depends on knowing who’s wielding the power over food and marketing.

Raj Patel is the author of Stuffed and Starved: The Hidden Battle for the World Food System. He says hunger and obesity are not just a matter of eating too little or too much. He said it has to do with what people are eating and the systems and institutions driving consumption.

“I have a very personal connection to the power in the food system. First of all, my parents are convenience store owners. So they sell the sweets and the fats and the sugars that are making the world more overweight. But at the same time my family is also suffering the consequences. There isn’t a man over 50 in my family who doesn’t have diabetes,” he said.

Patel is a fellow at the Institute for Food and Development Policy in Oakland, California and an honorary research fellow at the University of KwaZulu-Natal in South Africa.

There’s growing investment in agriculture around the world to feed an expected population of 9 billion by 2050. But as emerging economies grow in Africa and Asia, consumers in those regions are switching to a more Western diet. It’s a diet many blame for obesity, as well as diabetes and cardiovascular disease.

However, many others say that people have a choice as to what to eat. They don’t have to buy foods rich in fat, salt and sugar.

“The issue of choice is one that is often thrown around when it comes to power in the food system and really understanding this as a parent. Because as a parent we’re told that parents are the people who bring up children to make sensible choices. And I think that’s right. But if we’re going to be able to raise kids to make sensible choices in the food system then as parents we need a level playing field,” he said.

However, Patel said that’s not happening.

“When you look at the amount of money that is spent promoting food, the ratio of good food to junk food marketing is about 1 to 500. In other words, for every dollar that’s spent promoting fresh fruits and vegetables 500 is spent promoting junk food,” he said.

Just a handful of corporations, he said, control much of the global food market. It raises the question, he said, of what’s considered normal eating?

“You have kids growing up who think it is normal to be drinking 32 ounces of soda, basically sugar and empty calories. Children who are disconnected from where their food comes from and who are being raised in some very unhealthy eating habits.” He said.

Evidence can clearly be found in the United States.

‘One in three children who were born in the year 2000 will develop type 2 diabetes. And if we’re talking about children of people of color like myself then that’s near a one in two children will develop type 2 diabetes,” Patel.

Symptoms include increased thirst, fatigue, weight loss, blurred vision, sores that heal slowly and frequent infections. It can lead to cardiovascular disease, nerve, kidney, eye and foot damage. The main treatment is diet and exercise.

Patel said it’s happening in India, one of the emerging economies.

“India is a country that’s suffering [from] an epidemic of hunger at the same time as an epidemic of the kinds of disease that used to only happen in rich economies,” he said.

Modern diets, he said, are often very different from what our ancestors ate.

“If you excavate [a] Stone Age fireside, you don’t see empty packets of chips there. These chips are very new. The kinds of food that we eat today are in large part engineered and processed -- the foods that are rich in salt and fat and sugar. Those are the things our bodies are wired to crave and those are the things that are profitable to sell,” he said.

But he said there is hope for better nutrition.

“There’s an amazing kind of rebirth of the food movement in the United States and around the world of people who are excited to be reconnecting with growing their own food, with eating locally and sustainably and organically. And that’s a fight that’s well worth talking about as well, because it’s a way of reducing some of the problems associated with diabetes – the diseases of the modern food system,” he said.

What’s more, he said, consumers and communities in the U.S. and elsewhere are realizing they have a health and economic crisis on their hands linked to diet. He says they’re taking action by defining their own food and agriculture policies.